Gerwalk wrote:Yesterday night I checked the K-19 book (NatGeo once again) which has a photo (is from the same series of photos were the one posted above comes from) taken from a plane that clearly shows that the grooves weren't there at the time of the accident.

BTW: that Julliet is the one the Saratoga Foundation has in Providence, RI. It's worth visiting it!

But by the time of the 1972 incident the grooves do appear to be present, suggesting they were indeed a feature of some Hotel IIs only.